Bag filling apparatus with clamping rack



Dec. 14, 1965 s. LIPSCHUTZ BAG FILLING APPARATUS WITH CLAMPING RACK 4Sheets-Sheet 1 Filed Feb. 19, 1962 INVENTOR. S UN EY Ll P SCH UTZ BYCam-u W 1" ATTORNEYS.

Dec. 14, 1965 5, psc u' -z 3,222,846

BAG FILLING APPARATUS WITH CLAMPING RACK Filed Feb. 19, 1962 4Sheets-Sheet 2 INVENTOR.

SID N E Y LIPSCHUTZ WWW Dec. 14, 1965 s. LIPSCHUTZ BAG FILLING APPARATUSWITH OLAMPING RACK Filed Feb. 19, 1962 4 Sheets-Sheet 5 INVENTOR.

SIDNEY LIPSCHUTZ I28 I50 I52 I30 BY WWW ATTORNEYS. V

Dec. 14, 1965 s. LIPSCHUTZ BAG FILLING APPARATUS WITH CLAMPING RACKFiled Feb. 19, 1962 4 Sheets-Sheet 4 INVENTOR.

SI DNE Y Ll PSCHUTZ ATTORNEYS.

United States Patent M 3,222,846 BAG FILLING APPARATUS WlTll-l CLAMPHNGRACK Sidney Lipschutz, Philadelphia, Pa, assignor to Chemical Sales,line, Philadelphia, Pa, a corporation of Pennsylvania Filed Feb. 19,1962, Ser. No. 173,962

9 Claims. (Cl. 53266) This invention relates to an apparatus for fillingand sealing bags containing corrosive liquids, and also includes a novelclamping rack for supporting said bags while used with said apparatus.

It has been the prior practice in the industry to package corrosiveliquids such as acids or alkaline materials in containers consisting ofa relatively rigid outer unit made of fiberboard enclosing a flexibleinner unit of non-corrosive material such as polyethylene, celluloseacetate and the like. One such package is disclosed in copendingapplication Serial No. 110,179, filed May 15, 1961, now Patent No.3,137,433.

Packages of this type find particular utility when filled with sulphuricacid which is to be used in storage batteries. Currently electricstorage batteries are shipped without the acid and a predeterminedquantity of acid is separably shipped. When the battery is to be used,the container with the predetermined amount of sulphuric acid is emptiedinto each cell of the storage battery. In the alternative, the packagesmay be filled with large volumes of acid, such as five gallonquantities, and subsequently tapped with a non-corrosive probe. Acidfrom the package is then fed through a non-corrosive tube connected tothe probe into the individual battery cells. This tapping method ofdispensing acid is disclosed in the aforesaid copending applicationSerial No. 110,179, and forms no part of the instant invention.

In the past, filling of the packages was a long and tedious task. Theinner flexible container was first placed inside the outer rigidcontainer and subsequently filled with the acid. The filled package wasthen moved to a heat sealing station where the inner flexible packagewas heat sealed. Afterwards the outer package was glued closed. Themajor problem with this process was that it was a completely batchprocess and only one package could be handled at any one time.

The instant invention provides a semi-automatic apparatus which greatlyfacilitates the filling and sealing of the packages with a correspondingdecrease in the amount of time required.

It is therefore an object of this invention to provide a novel apparatusfor filling and sealing a package containing a corrosive material.

It is a further object of this invention to provide a rack forsupporting a flexible bag to be filled with a corrosive material.

It is a further object of this invention to provide an apparatus forsupporting, filling and sealing a flexible container with all parts ofthe apparatus being pneumatically actuated.

The foregoing, as well as other objects of this inven tion, are achievedby providing an apparatus comprising an endless conveyer, at least onebag supporting rack on said conveyer, a filling station on saidconveyer, and a heat sealing station, said bag supporting rack having aclamping bar which is air actuated.

In another aspect of this invention, there is provided a bag supportingrack comprising a frame member, a pair of clamping bars associated withsaid frame member, at least one of said bars being movable toward andaway from the other bar and means for moving said movable bar towardsaid other bar, said moving means including a spring actuated pneumaticpiston.

3,222,84fi Patented Dec. 14, 1965 ICC? Other objects and many of theattendant advantages of this invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a perspective view of the bag-supporting rack of thisinvention;

FIG. 2 is a sectional view taken along line 22 of FIG. 1 with a bagshown in phantom;

FIG. 3 is a front elevational view of the bag supporting rack shown inFIG. 1;

FIG. 4 is a plan view of the bag supporting rack shown in FIG. 1;

FIG. 5 is an enlarged sectional view of the clamping rods with a bagheld therebetween;

FIG. 6 is a diagrammatic sectional View of the twoway valve used on thebag supporting rack;

FIG. 7 is a diagrammatic sectional view of the quick exhaust valve usedon the bag supporting rack;

FIG. 8 is a diagrammatic sectional view of the clamping cylinder used onthe bag supporting rack;

FIG. 9 is a diagrammatic plan view of the apparatus of this invention;

FIG. 10 is a diagrammatic front elevational view of the apparatus shownin FIG. 9;

FIG. 11 is an enlarged, partial, diagrammatic sectional view taken alongthe line 88 of FIG. 10;

FIG. 12 is an enlarged, partial, diagrammatic sectional view taken alongthe line ill-12 of FIG. 10;

FIG. 13 is an enlarged, partial, diagrammatic sectional view taken alongthe line 13-413 of FIG. 10; and

FIG. 14 is an enlarged, partial, diagrammatic sectional view taken alongthe line 14-14 of FIG. 10.

Referring now in greater detail to the various figures of the drawingswherein similar reference characters refer to similar parts, a bagfilling apparatus embodying the present invention is generally shown at20 in FIG. 9. The apparatus basically comprises an endless conveyer 22and includes a bag loading station 24, a bag filling station 26, a heatsealing station 28, and an unloading station 30.

Endless conveyer 22 is a track having elongated parallel sides 32 andcurved ends 34.

The flexible bags to be filled are moved from station to station alongthe conveyor 22 by a bag supporting rack indicated generally at 36. Asseen in FIG. 1, rack 36 comprises a frame 38 which includes a pair ofangle bars 40, each of which is bent at a right angle. Angle bars 4% arelaterally spaced from each other and are connected at their upperportions by a bridging angle bar 42. As seen in FIG. 1, bridging bar 42includes one face 44 which is welded or otherwise secured to the anglebars 40. A second face 46 of bar 42 extends perpendicularly outward fromthe upper edge of face 44 and thus lies in a horizontal plane. As seenin FIG. 1, angle bars 40 include vertical sections 48 and horizontalsections 50 which are at right angles to the vertical sections. Bar 42is secured to the upper portion of vertical sections 48. A fiat bar 52is welded, or otherwise secured, to the lower portions of sections 48.Secured to the outer surface of fiat bar 52 are a plurality of roundnumbs 54. Usually three nubs are used, with one being placed adjacenteach vertical section 48 and one in the center of bar 52. The purpose ofthese nubs will be explained hereinafter.

Secured to the lower surfaces of the outer portions of horizontalsections 50 is an angle bar 56. As seen in FIG. 2, angle bar 56 includesa horizontal surface 58 and a vertical surface 60 extendingperpendicularly downward from the horizontal surface.

A generally U-shaped bar 62 extends horizontally outward from horizontalsection 50. Bar 62 includes parallel side legs 64 and bridging section66. A horizontal plate 68, which is integral with legs 64 and bridgingsection 66, or welded thereto, extends inwardly from the top of thebridging section along a substantial portion of legs 64 and terminatesabout the distance between bridging section 66 and vertical surface ofangle bar 56 (see FIG. 2). As seen in FIG. 5, a rod 70, which issubstantially square in cross section, is secured to the inner edge ofplate 68. Referring again to FIG. 1, it is seen that plate 68 issubstantially rectangular in shape but includes an arcuate recess 72 atone end thereof. The purpose of this recess will be explainedhereinafter.

Secured to the center of the top of horizontal surface 58 of angle bar56, is a clamping cylinder 74. Cylinder 74 includes a piston rod 76which extends horizontally outward therefrom. A rectangular rod 78 isperpendicularly secured to the end of piston rod 76. The rectangular rod78 is secured to the vertical face 80 of angle bar 82 (see FIG. 2).Angle bar 82 also includes a horizontal face 84. A square rod 86 issecured to vertical face 80 on the side opposite rectangular rod 78(FIG. 5). As seen in FIG. 5, a pair of arcuate rubber sleeves almostcompletely cover rods 70 and 86. The purpose of the rubber sleeves is tosecurely engage the upper end of a flexible bag 90, such aspolyethylene, without tearing the bag. As seen in FIG. 5, sleeves 88 areshown as having a corrugated surface. The purpose of this surface is toprovide a more secure grip on the bag and thus prevent slippage when thebag is filled. Sleeves 88 can be made of any resilient material having ahigh coefficient of friction, such as natural or synthetic rubber.

It is thus seen that a bag 90 is supported in rack 36 by means of thepressure transmitted from clamping cylinder 74 through piston rod 76 andto rod 86. Since rod 70 is stationary, the amount of pressure applied isdirectly dependent upon the pressure of the air supplied to thepneumatic cylinder 74. In order to guide the rod 86 in its reciprocatingmovement when clamping and unclamping a bag, a pair of guide means 92are provided. Each guide means 92 includes a vertical plate 94 which issecured to horizontal surface 58 of angle bar 56. A horizontal shaft 96is slidably mounted within plate 94. One end of shaft 96 is secured tothe vertical face 80 of angle bar 82 by bracket 98. As seen in FIG. 1,plates 94 are positioned on opposite sides of clamping cylinder 74.

As pointed out above, clamping cylinder '74 is pneumatically actuated.The structure of clamping cylinder 74 is diagrammatically illustrated inFIG. 8. Cylinder 74 basically comprises a cylindrical housing 100.Integral with said housing is a mounting plate 102 having holes 104therein. The purpose of the plate is to secure the mounting cylinder tohorizontal surface 58 by means of bolts passing through holes 104. Therear wall 106 of the cylinder includes a centrally located threaded hole108, through which the inlet air passes. A piston assembly 110 islocated within cylindrical housing and adjacent hole 108. A U-sectionpiston cup 112 provides an air seal for the piston assembly. Securedwithin the piston assembly and slidably mounted in front plate 114 ispiston rod 76. Telescopingly engaged over the piston rod and abuttingfront plate 114 and piston assembly is a compression spring 116.

In operation of the clamping cylinder, air is fed in through hole 108.This, in turn, causes piston assembly 110 to move forward, which, inturn, urges piston rod 76 forward. The piston cup substantiallyeliminates any air loss into the remainder of the cylindrical housing.As soon as the air supply is cut oif, and the pressure returns toatmospheric, compression spring 114 causes immediate piston return. Itshould also be noted that the air hole 108 is on the same center aspiston rod 76, which insures maximum effectiveness. One type of clampingcylinder that can be used for this purpose is Schrader No. 3352 A whichis shown in Catalog #50 of A. Schrad- 4 ers Son, Division of ScovillMfg. Co., Inc., Brooklyn 38, N.Y.

The controls for clamping cylinder 74 basically comprise a two-way valve118 and a quick exhaust valve 120.

Two-Way valve 118 is shown diagrammatically in FIG. 6 and basicallycomprises a cylindrical valve housing 122 having a threaded inlet port124 and a threaded outlet port 126. Housing 122 includes a downwardlyextending wall 128 adjacent inlet port 124, and an upwardly extendingwall 130 adjacent outlet port 126. These two walls meet to form acircular hole therebetween, through which the air entering the housingwill pass to the outlet port. Surrounding this hole and fixedly securedto walls 128 and 130 is a washer 132. A pair of holes 134 are providedin the upper portion of housing 122. The purpose of these holes is toprovide a means for securing the valve to the apparatus in which it isto be used. A pair of bridges 136 (one shown) are integral with housing122. These bridges are spaced apart a distance sufficient to receive alever 138. Lever 138 is pivotally mounted between the two bridges 136 bymeans of a spring pin 140. Bridges 136 are also provided with a pair ofholes 142 through which pass a pair of spring pins. It is thus seen thatlever 138 is pivotally mounted between the two bridges and can be heldin any set position by means of the spring pins. Lever 138 also containsa cam surface 144 at the lower end thereof, the purpose of which will beexplained hereinafter. A nut 146 is threadedly engaged in the topportion of housing 122. Slidably mounted within nut 146 is a plunger148. Secured to the lower end of plunger 148 is a circular closure plate150. Closure plate 150 is of a diameter which is slightly larger thanthe interior diameter of washer 132. A compression spring 152telescopingly engages the lower tip of plunger 148 and abuts against theunder surface of plate 150 and the bottom interior surface of housing122.

In operation, outside air is fed into port 124. Air is prevented frompassing through the valve by closure plate 150. However, by raisinglever 138 from the position shown to a position which is slightly to theleft of vertical, the cam surface 144 will depress plunger 148. Thiswill, in turn, depress plate 150, thereby opening the hole formedbetween walls 128 and 130. The incoming air will then be free to passthrough the hole and out of outlet port 126. The flow of air can beimmediately stopped by returning lever 138 back to the position shown.It is to be understood that the use of the lever can be varied byvarying the cam surface. Thus, by changing the cam surface, the valvecould be held in an open condition when the lever is in a position shownin FIG. 6. A suitable two-way valve is Schrader valve No. 3414 shown inSchrader Catalog #50.

A diagrammatic view of quick exhaust valve 120 is shown in FIG. 7. Thisvalve basically comprises an upper inlet housing 154 and a lower outlethousing 156. Inlet housing 154 includes threaded inlet port 158. Loweroutlet housing includes threaded outlet port and threaded exhaust port162. The upper housing 154 is secured to lower housing 156 by means ofscrews 164. An air tight seal can be effectuated by means of a gasket166. An air chamber 168 is formed between the upper and lower housings.A diaphragm 170 extends laterally across the air chamber and serves toseal exhaust port 162. It should be noted that diaphragm 170 issufiiciently wide to cover the exhaust port but does not extend acrossthe entire width of air chamber 168.

In operation, the incoming air is fed into port 158. The continuedpressure of the incoming air forces diaphragm 170 over exhaust port 162thereby sealing it. When the exhaust port is sealed, the air then passesthrough outlet 160. When the supply of incoming air is cut off,diaphragm 170 will be raised slightly and all of the air within thevalve and the system will be quickly exhausted through port 162. Asuitable quick exhaust valve is Schrader valve No. 3340 shown inSchrader Catalog #50.

The operative connections of the various valves are shown in FIGS. 1 to4. As seen in FIG. 2, an angle bar 172 is welded, or otherwise secured,to the lower edge of vertical surface 60 of angle bar 56. Secured withinangle bar 172 is a T-coupler 174 having an inlet port 176, an outletport 178 and a branch outlet port 180. A length of air hose 182 isconnected to inlet port 176, and a second length of air hose 182 isconnected to outlet port 178. An air hose 184 connects branch outletport 180 with inlet port 124 of two-way valve 118 (see FIGS. 2 and 4.)

Two-way valve 118 is connected to frame 38 by means of vertical plate186 which is secured to horizontal surface 58 (FIG. 1). The connectionis accomplished by means of bolts 188 which pass through the plate andholes 134 in valve 118. This connection is shown in FIGS. 1 and 4. Anair hose 190 connects outlet port 126 with inlet port 158 of quickexhaust valve 120. A rigid pipe 192 connects outlet port 160 of valve120 with inlet port 108 of cylinder 74. Rigid pipe 192 also serves tosupport valve 120.

As seen in FIGS. 1 and 2, endless conveyor 22 is basically in the shapeof an inverted U having parallel sides 194 and bridging section 196integral therewith. Extending perpendicularly inward from sides 194 areflanges 198. These flanges are spaced apart by gap 208. Flanges 198 forma track on which racks 36 ride as they are moved around endless conveyer22.

Racks 36 are slidably secured in conveyer 22 by means of roller assembly202. Roller assembly 202 includes a bracket 204 having an upperhorizontal leg 286, a lower horizontal leg 288, and a vertical leg 218connecting the horizontal legs. Bracket 204 is secured to vertical shaft212, which is, in turn, secured to horizontal face 46 of angle bar 42.The securements can be obtained by welding or any other known means. Asseen in FIG. 1, each rack contains two roller assemblies 202.

A pair of shafts 214 are horizontally secured in horizontal leg 206. Apair of rollers 216 are rotatably mounted on the outer ends of eachshaft 214. A second pair of shafts 218 are vertically secured betweenupper horizontal leg 206 and lower horizontal leg 288, and on oppositesides of vertical leg 210. A vertically disposed roller 220 is rotatablymounted on each of shafts 218.

Rack 36 is supported on conveyer 22 by rollers 216 which movelongitudinally along flanges 198 (FIG. 2). Lateral movement of rollers216 is prevented by rollers 220 which are aligned in gap 288. Rack 36 ismaintained in its set vertical orientation by means of endless bar 222which extends around the entire perimeter of endless conveyor 22. Asseen in FIGS. 1 and 2, rounded nubs 54 abut against endless bar 222. Bar222 and nubs 54 are provided with a coating of lubricant to maintain afreely sliding contact.

In operation, a flexible bag 90 is loaded on to the rack 36 at loadingstation 24 (FIG. 9). A jig 224 is used to obtain the proper vertical andhorizontal orientation of the bag 98 within the rack 36. A suitable,flexible bag 90 can be that disclosed in the aforesaid copendingapplication Serial No. 110,179. As seen in FIGS. 9, 10 and 11, jig 224includes a pair of horizontal bars 226 which are secured to bridgingsection 196 of conveyor 22. A vertically extending shaft 228 is securedin the outer end of each bar 226 by means of nuts 230 which are placedabove and below the bar. The lower end 232 of the shaft 228 is threaded,and a bar 234 is secured to said lower end. Bar 234 includes an upperhorizontal portion 236 adjacent threads 232, a vertical portion 238, anda lower outwardly extending horizontal portion 248. Portion 236 containsa hole therein and is secured to shaft 228 by nuts 242. The verticalorientation of bar (FIG. 12).

234 can be adjusted by raising and lowering nuts 242 on threaded portion232. As seen in FIG. 11, two bars 234 are provided and lower portions240 are at exactly the same height.

A bag is inserted in the rack by first separating rods 70 and 86. Thisis accomplished by cutting off the air supply to clamping cylinder 74which will cause piston rod 76 to retract. The method of cutting off theair supply is accomplished by moving lever 138 of valve 118 to theposition shown in FIG. 6. Bag 90 is then inserted between rods 78 and 86by lifting it through the under side thereof. The height of the bagwithin the rack is determined by abutting the upper edge of the bag 98against the lower edges of horizontal portions 240 of bar 234. When thebag has attained the desired orientation, two-way valve 118 is opened,which will cause air to enter clamping cylinder 74. The air pressurewill force piston rod 76 forward thereby clamping the bag securely inplace. So long as the air pressure is maintained within clampingcylinder 74, the two rods 70 and 86 will remain clamped together.

With the bag clamped securely within rack 36, the rack is then moved byhand along the conveyor to filling station 26. At the filling station aplurality of bags (three shown) are filled automatically. The type offilling apparatus used is disclosed in Patent No. 2,967,004. Since alldetails of the apparatus are disclosed in said patent, the fillingapparatus is shown only schematically herein. The apparatus basicallyincludes a storage tank 244, a plurality of rigid egress lines 246, anda flexible tube 248 secured to the open end of each egress line. Sincecorrosive liquids are handled in the tank, all the pipes or tubes aremade of corrosion resistant material such as neoprene. Tank 244 issupported by the frame supporting conveyor 22. As seen in FIG. 12,egress line 246 rests on horizontal face 196 of conveyer 22 and is bentaround at its outward end and held in place by a pair of angle brackets250. Flexible tubing 248 is secured to egress line 246 by any suitablenon-corrosive connecting means.

The filling of the bags is illustrated in FIGS, 10 and 12. As seen inFIG. 4, when bag 98 is clamped in place, one end of the bag forms anopen loop 252. The purpose of arcuate recess 72 in plate 68 is toaccommodate the open loop. After three racks are arranged in tandem, aflexible tube 248 is placed in the open loop of each bag The dispensingapparatus is then hand actuated and sulphuric acid 254, or othercorrosive liquid, is then dispensed in a measured amount into each ofthe bags. As explained in the aforesaid Patent No. 2,967,004, thedispensing and the measuring of the liquid are pneumatically controlled,whereby it is unnecessary for any corrosive metal parts to be contactedby the liquid.

After the bags are filled, they are moved to the heat sealing station28. The heat sealing station includes a heat sealing device 256, a coldsealing device 258 and a control panel 260. The heat sealing device andthe cold sealing device and their controls are well-known to the art andtheir specific structure form no part of this invention.

As seen in FIG. 13, the heat sealing device includes a supportingbracket 262 which has a centrally located recess 264 in the lower sidethereof. A pair of pneumatic cylinders 266 are secured to bracket 262with one located on each side of recess 264. Each cylinder 266 isprovided with an air inlet tube 268 and an air exhaust tube 270. Anelectric cylindrical heating iron 272 is secured to the 62d of eachpiston rod 274 of the pneumatic cylinder. When a filled bag is placedadjacent arcuate recess 264, air is fed into pneumatic cylinders 266,thereby causing heating irons 272 to converge in the direction of thearrows in FIG. 13. The irons are kept in contact with the upper edge ofthe bag 90 until an eflective heat seal is obtained. The air supply tothe cylinders is then cut off causing the heating irons to Withdraw.

. previously made.

After the heat seal has been effectuated, the rack is then moved to thecold sealing device. The cold sealing device is shown schematically inFIG. 14 and includes a supporting bracket 276. Secured to one lower endof bracket 276 is a pneumatic cylinder 278 having air inlet tube 280 andair exhaust tube 282. Secured to the other lower end of bracket 276 is arod 284 through which is a coolant circulated. When air is supplied tocylinder 278, piston rod 286 having pressure plate 288 thereon is forcedforward in the direction of the arrow. This clamping action serves tocool and set the heat seal which was The timing on the cold seal andheat seal is synchronized so that two bags may be accommodated at onetime, as seen in FIG. 10.

After the cold sealing step, the rack is moved to the unloading station30 (FIGS. 9 and 10). A corrugated box 290 is placed under bag 90 and theclamping jaws 70 and 86 are opened, thereby releasing the bag. Thisopening is accomplished by closing two-way valve 118 which causes theair in the system to be immediately released through quick exhaust valve120 and piston rod 76 to retract. The box 290, with filled and sealedbag 90 therein, is then placed on conveyor 292 on which the box will besubsequently sealed and loaded for shipment. The empty rack is thenpushed by hand around the conveyer 22 in the direction of arrow 294where it will subsequently be reloaded at loading station 24,

Conveyer 22 is conveniently suspended from the ceiling by means of bars296. The purpose of the overhead suspensions is to allow for freemovement of the air hoses 182 which are suspended from each of the racks36. As seen in FIG. 10, all of the racks are connected in series along asingle air hose 182 with a single source of air 298 entering hose 182through T-connector 300 and hose 302. Thus, the air will be continuallypassing through T- coupler 174 of each rack. The admission of air to theclamping cylinder 74 of any particular rack is controlled by two-wayvalve 118. It should also be noted that enough slack is left in eachsection of hose 182 between adjacent racks to permit their being movedindividually from one station along the conveyer to another. It shouldalso be noted that the filling station and hot and cold sealing devicesare also pneumatically operated and can draw their air from the samesource as the bag supporting racks. Generally an air line pressure of100 p.s.i. is used, which will give a clamping pressure of 300 p.s.i.for each clamping cylinder.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

What is claimed as the invention is:

1. An apparatus for filling a flexible bag with corrosive liquidcomprising an endless conveyor, a plurality of bag supporting racks onsaid conveyor, each of said racks including a T-coupler for receivingair thereto, and a plurality of lengths of hose connecting the T-couplerof each rack with the T-coupler of an adjacent rack whereby air may besupplied to each of said racks through a series connection, each of saidracks having a clamping bar which is air actuated, a filling device forfilling said bags with a corrosive liquid, and a heat sealing assembly.

2. The apparatus of claim 1, and further including a bag loadingstation, said bag loading station having a jig thereat for determiningthe vertical and horizontal orientation of the bag when placed withinthe rack.

3. The apparatus of claim 1 wherein said filling device and said heatsealing assembly are pneumatically actuated.

4. The apparatus of claim 1 wherein each said bag supporting rackcomprises a frame member, a pair of clamping bars associated with saidframe member, at least one of said bars being movable toward and awayfrom the other bar, and means for moving said movable bar towards saidother bar, said moving means including a spring actuated pneumaticpiston.

5. A bag supporting rack comprising a frame member, a pair of clampingbars associated with said frame member, at least one of said bars beingmovable toward and away from the other bar, means for moving saidmovable bar toward and away from said other bar, said moving meansincluding a spring actuated pneumatic piston, a T- coupler secured tosaid frame, a two-way valve secured to said frame, hose means connectingsaid coupler to said two-way valve, a quick exhaust valve, hose meansconnecting said two-way valve to said quick exhaust valve and meansconnecting said quick exhaust valve to the air inlet side of a clampingcylinder which houses said pneumatic piston,

6. The rack of claim 5 and further including a resilient sleeve coveringa substantial portion of each of said clamping bars.

7. The bag supporting rack of claim 5 and further including a rollerassembly on said frame, said roller assembly being adapted to slidablysupport said rack within an endless conveyer.

8. The rack of claim 7 and further including a plurality of round nubson said frame, said nubs being adapted to abut against an endless bar ofsaid conveyer where-by the vertical orientation of the rack will bemaintained on the conveyer.

9. A bag supporting rack comprising a frame member, a pair of clampingbars associated with said frame member, at least one of said bars beingmovable toward and away from the other bar, said other bar being securedto a rectangular plate which is, in turn, secured to said frame, saidother bar extending along a major portion of the width of said plate,with said plate defining an enclosed recess at the portion wherein saidother bar is absent, and means for moving said movable bar toward andaway from said other bar, said moving means including a spring actuatedpneumatic piston.

References Cited by the Examiner UNITED STATES PATENTS 2,125,758 3/1938Waters.

2,491,226 12/1949 St. Jacques et al. 198-19 X 2,582,178 1/1952 Thompson198-19 2,656,964 10/1953 Detrez 198-19 2,736,479 2/1956 Mclnerney 198-19X 2,754,644 7/1956 Vergobbi et al 53-29 2,787,875 4/1957 Johnson 53-373X 2,900,774 8/1959 Henriksen 53-126 2,967,004 1/ 1961 Lipshultz et al.222- FRANK E. BAILEY, Primary Examiner.

ROBERT A. LEIGHEY, Examiner.

1. AN APPARATUS FOR FILLING A FLEXIBLE BAG WITH CORROSIVE LIQUIDCOMPRISING AN ENDLESS CONVEYOR, A PLURALITY OF BAG SUPPORTING RACKS ONSAID CONVEYOR, EACH OF SIAD RACKS INCLUDING A T-COUPLER FOR RECEIVINGAIR THERETO, AND A PLURALITY OF LENGTHS OF HOSE CONNECTING THE T-COUPLEROF EACH RACK WITH THE T-COUPLER ON AN ADJACENT RACK WHEREBY AIR